The purpose of the molecular probes and imaging core is 1: to synthesize imaging probes (opfical, MR and multimodal) capable of cell tracking, fate mapping, and reporting on molecular events, and 2: to supply imaging expertise and equipment to detect these probes in vivo and in vitro. The four projects within the PPG share a number of interrelated goals in terms of functional and molecular imaging. The purpose of the imaging core is to provide a centralized source of chemical and imaging expertise to the investigators of the PPG, and to develop imaging protocols and techniques that will benefit all the investigators and reduce the amount of redundant effort needed to achieve the imaging goals of the projects.